CSV

CSV Structure Validator

Finds ragged rows, duplicate column names and unnamed columns, and reports where they are.

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How to use this tool

  1. Paste or open the file you want checked.
  2. Select Check structure.
  3. Work through the reported row numbers in your source file.

What csv validator does

The most common CSV fault is a row with the wrong number of fields, usually caused by an unescaped comma or an unbalanced quote somewhere upstream. A loader will either reject the whole file or, worse, silently shift every value one column to the left from that point on. This validator reports each offending row by number so you can go straight to it.

It also checks the header, because two columns with the same name and a column with no name at all both cause trouble later: the first makes a lookup ambiguous, the second produces an unusable key when the file is converted to JSON or loaded into a table. Neither is invalid CSV as such, which is exactly why they tend to survive all the way into production.

Frequently asked questions

A row whose field count differs from the header. That is almost always caused by an unescaped delimiter or an unbalanced quote earlier in the file.

No, this checks structure only. For value-level checks such as types, ranges and completeness, use the column profiler.

Duplicate names are legal in a CSV file but ambiguous everywhere else. Converting to JSON drops all but one of them, and most database loaders reject the file outright.